I have a button set-up where on = record and off = play, another on = stop and second function = erase, one for undo and one each for half and reverse using step commands to cycle them on and off where there step name is displayed on the Liquid foot screen, I may change these 2 back to on and off values rather then steps. With the Liquid foot you can set the little screens to be different colors based on their state ie on, off or bypassed.
Currently I have a separate page setup for the looper which has buttons to get to my setlist page, fx page and song page, each of those has a button to get me back to the loop page. I can change rigs, add effects and have an expression pedal set-for wah and another which can be gain or volume or anything else I want to figure out. Each preset in the Liquid Foot can have something like 20 functions defined, then when you get to the song level you can have another 10, as an example I send cc's to the Kemper to change the rig, cc's to change settings on my voicelive2 based on the preset selected and send a command to ableton to change the video I have running when a preset is selected within a song. The editor for the LF has an area to set-up 16 devices so you can do a ton of things and that gives lots to play with lol
Getting back to the looper, I have noticed that the loop volumes can change based on the rig being selected, for example if I start a loop with a clean sound and switch to a rig with boosted volume for a solo the volumes can get get loud, I have been using the expression to go from clean to dirty instead. Anyway I am still playing around to see what works, looking at the manual, shouldn't there also be a command to trigger the loop?